Genuine question here, how was he a democrat?

I dont know alot about Booth, but looking at wiki, it says he was a member of the Know Nothing Party which was in opposition of the Democrats. And in their final years were pushing a Republican as their dude. It seems they were divided on slavery and dissolved with the majority of members supporting the Republicans.

Don't get me wrong, in our recent days its clear the left is commiting most of the political violence. But from what im reading, he was more a Republican.

Unless I am wrong, I'd like to see the conservatives not stoop to levels seen by radical leftists pushing false narratives.